/*
*
* Copyright (c) 2011 Vaulting Systems International
* 
* Permission is hereby granted, free of charge, to any person obtaining a copy 
* of this software and associated documentation files (the "Software"), to deal 
* in the Software without restriction, including without limitation the rights 
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies 
* of the Software, and to permit persons to whom the Software is furnished to do  
* so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in all  
* copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, 
* INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A 
* PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT 
* HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION 
* OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE  
* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*
*/
package com.ekeymanlib.util;

import java.security.NoSuchAlgorithmException;
import java.security.SecureRandom;
import java.util.UUID;

public class KeyUtils {

	public static byte[] generateKey(int keyBytesLength){
    	return generateBytes(keyBytesLength);
	}
	
	public static String generateAppDeviceKey() {
		UUID vendorKey = UUID.randomUUID();
		return vendorKey.toString();
	}
	
    public static byte[] generateSalt(int saltLength) {
    	return generateBytes(saltLength);
    }      
    
    public static byte[] generateIv(int ivLength) {
    	return generateBytes(ivLength);
    } 
	
    private static byte[] generateBytes(int bytesLength) {
    	byte[] bytes;
		try {     	
    	
	    	SecureRandom random = SecureRandom.getInstance("SHA1PRNG");
	    	bytes = new byte[bytesLength];
	    	random.nextBytes(bytes);
		}
		catch(NoSuchAlgorithmException x) {
			bytes = null;
		}

    	return bytes;
    } 
    
    public static int generateIterationCount(int maxCount) {
    	int i = 0;
		try { 
	    	SecureRandom random = SecureRandom.getInstance("SHA1PRNG");
	    	i = random.nextInt(maxCount);
		}
		catch(NoSuchAlgorithmException x) {
			i = 0;
		}

    	return i;
    }   
    
}